Heaslip heard the news that the powerful Australian is returning to his homeland after a stunning season with the Dubliners that culminated in him helping them to become the third Irish province to win the Heineken Cup.
"Rocky is an awesome player - one of the best I've ever played with. It was great to have him at Leinster for the year," said Heaslip.
"But we all understand his desire to carry on playing international rugby and that's why he is going home. He really bought into the whole Leinster philosophy and was a huge asset for us."
But while the Heineken Cup winners will have to defend their title without the Aussie back row powerhouse next season, they will have another giant in the making in their back row to take on his leadership role.
Heaslip had a superb first full start in a Lions jersey as the tourists' spanked the Golden Lions 74-10 in Johannesburg last night. Even though he didn't get among the try scorers, the Leinster and Ireland No 8s work rate around the fringes caught the eye.
"It seemed like all the other back row men were getting tries, but I guess our hard work paid off. We were saying that we needed to set the tone as an eight to give the backs a platform and that's what we did," said Heaslip.
"We know how we want to play and everyone is buying into that. We all know each other's names now and things are going well.
"To make such a huge improvement from the weekend has made us happy, but we have a lot to work on. Every game is a step up now and we have to demand more of ourselves every time we play."
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